White tea is produced from varietals that yield whitish sprouts and leaves. The original varietal for white tea is called chaicha and is still used for some white tea, it does not have an abundance of the fine white hairs that white tea is famous for. The chaicha varietal has been supplanted somewhat by other varietals such as Fu Ding Da Hao, Fu Ding Da Bai, and Shui Xian.
The pale color of white tea is a product of two factors: the varietal and the immaturity of the tea leaves. Only the buds and young leaves are used for white tea. They are even sometimes shaded for several weeks prior to harvesting to further reduce the chlorophyll content.
White tea is hand harvested during the springtime. Weather conditions must be cool and dry. Less than ideal conditions will adversely affect the quality of tea, and for this reason some years produce better white tea than others.
The highest grades of white tea are made from pluckings which keep the two leaves and the bud intact. These must all be covered with tiny hairs for making the best white teas which are graded as Yin Zhen Bai Hao (Silver Needle) or Bai Mu Dan (White Peony). Lesser grades of white tea are produced from leaves which do not meet these standards.
After the leaves are plucked they are withered in the sun before transferring them indoors for more controlled withering. The withering process halts the oxidation which causes the leaves to turn dark.
The balance between indoor and outdoor withering has a profound affect on the quality of the finished tea. The tea processor decides on the withering time by judging weather conditions such as temperature and humidity.
After withering the leaves are graded and then baked to remove excess moisture. Baking time must also be precisely controlled.
This minimal processing is the reason why white tea is higher in health-promoting catechins than other types of tea. These health properties of white tea is one of the major reasons for its newly-found popularity in the west, but as tea drinkers in America and Europe become more sophisticated the unique taste of white tea becomes more important to its widening acceptance.